Windshield cleaner system



available with the primary pressure source.

Patented May 9, 1944 UNITED STATES PATENT OFFICE Erwin C. Horton,Hamburg, Buflalo, N. Y.. assignors to poration, Buffalo, N. Y.

and Anton Ralll Trico Products Cor- Application January 1, 1942, SerialNo. 425,362

among other things to insure quick starting of v I 3 Claims.

This invention relates to a fluid pressure vehicle accessory system andmore particularly to novel control means therefor.

In the operationoi fluid pressure systems generally, it is desirable toprovide a reserve supply of pressure fluid, particularly where theprimary fluid pressure source is variable in its output. While theprinciples of the present invention are general in their application inthis field, a particular accessory system embodying the underlyingprinciples of the present invention is set forth herein by way ofexample. However, while particular reference is had throughout theensuing specification to a fluid pressure. windshield cleaner systemactuated from a source of subatmospheric pressure, itis to be understoodthat analogous pressure operated accessories may be substituted andpositive pressure sources may be employed without departing from theprinciples and teachings of the invention. Nothing herein is to beconstrued as limiting the, spirit or scope of the invention excepting asit is deflned in the appended claims.

Referring to the disclosed example of the application of the principlesof the present invention; vacuum operated automatic windshield cleanersfor vehicles are widely used and conventionally include operating motorsarranged for two conditions of fluid pressureapplication; one whereinthe pressure is so applied as to oscillate or otherwise move theclearing means substantially continuously on a windshield surface; andanother wherein the pressure is so applied as to continuously hold thecleaning means in a predetermined arrested position, the latter beinggenerally referred to as a parked condition of the windshield cleanerand prevailing whenever the cleaner is not being used and differentialfluid pressure is available.

It is desirable, particularly where the source of differential pressureis variable in output, to

the windshield cleaner when its manual control is actuated to begincleaning.

By virtue of the system oi the present invention 'the stateddisadvantage is entirely eliminated since the fluid differentialpressure of the storage vessel, while conveniently available for useduring periods of windshield cleaner or accessory operation, is closedoil' from the accessory when the accessory-is stopped.

It is an object of the invention to attain the desired fluid pressurerelationship automatically and with no requirement for special attentionof the operator. A further object of the invention resides inaccomplishing the' desired cutoff between the storage vessel and theaccessory while at the same time, retaining fluid communication betweenthe primary fluid pressure source and the storage vessel to the extentthat the latter may be replenished by the former. whenever the former isdeveloping fluid differential pressure greater in degree than thatalready present in the vessel. It is further contemplated that otheraccessories may be operated from the fluid pressure supply of thesystem.

' Other objects and advantages attendant upon use of the teachings ofthe instant invention will appear to those skilled in the art from aperusal employ a storage vessel, either interposed inthe fluid conduitbetween the pressure generating source and the accessory motor orassociated in the system in such other manner as to be jointly Adisadvantage of prior systems of this general nature has resided in thefact that application of parking and holding pressure to the accessoryin an entirely leak-proof manner has not been commercially possible. Asa result the stored fluid pressure becomes dissipated during periodswhen the primary pressure generator is inactive or relatively so. It isdesired that the pressure differential built up be retained for usefulwork,

of this specification in connection with the accompanying drawing,wherein:

Fig. i is a somewhat diagrammatic view of an entire windshield cleanersystem comprising one form of the present invention and showing thecontrol element thereof in longitudinal cross section; and v Fig. 2 is across sectional view taken approximately on line 22 of Fig. 1.

Throughout the several figures of the drawing like characters ofreference denote like parts and the numeral l0 designates a. windshieldwiper motor connectible with a pair of fluid conduits Ii and I2, theformer being connected with the -m'otor in such manner as to cause themotor to oscillate an associated windshield wiper arm is, and the latterbeing connectible with the motor to move the arm i3 to parked positionand hold the same in such position. v

When it is desired to construct a windshield wiper motor of the instanttype, that is, one wherein only two selectively connectible fluidconduits lead from the manual control means to the-motor, it hasheretofore been necessary to provide special means to insure parking inspite of theparticular position which the conventional automaticreversing valve may chance to assume at the'instant when the manualcontrol-is moved from operating to parked position. Such means usuallycomprise specialap- .paratus for automatically venting one side of ingto which of a pair of fluid conduits is energized.

Referring to Fig. l, the source of fluid differentlal pressure in thepresent instance comprises I an intake manifold M of an internalcombustion engine (not shown) in which manifold the fluid pressure issub-atmospheric during periods of normal engine operation. Asub-atmospheric pressure storage chamber or vacuum reservoir isdesignated l5 and a-conduit it connects between the manifold l4 and thereservoir 18, there being provided a-unidirectional check valve I! whichpermits fluid flow from the reservoir to the manifold l4, to tend toevacuate the former, but which prevents retrograde fluid flow.

The manual control means of the present system is designated generally28 in Fig, I and may comprise a generally cylindrical body 2| having anaxial bore22. The body 2i maybe supported by the instrument'panel of avehicle as at '23, and such support may-be effected by providing anannular flange 24 on the body 2! and a threaded end portion 25 forprojection through a suitable opening in'the instrumentpanel andengagement with a retaining nut 28.

A plurality of annular valvlng elements are disposedwithin the bore 22of the body member 2| and are all retained for joint axial movement by astem 28 in amanner which will presently appear. The stem 28 extends fromthe body trol stem 28 and the knob 30.

Whenever the fluid differential pressure in the member 2! and ispreferably non-circular at its terminal extending portion-as at 29,wli'ereby a suitable manipulating knob 30' may be secured thereto andrendered'readily'non rotatable with respect to the stem 28.

Adjacent the enlarged non-circularportion 23,

the stem 28' is provided with an annulus "which supports -a cup-likepacking '33 which prevents fluid fiow between the interior of the bore22 and the atmosphere through the lefthand end of the bore. To the rightof the packing 33 the stem 28 receives a sleeve-like element 35 which issecured against rotation'with respect to the stem 28 by'means of aprotuberance 36 which engages aflattened portion of stem 28. 1A5 will beseen from the detailed cross sectionjFig. 2,

the sleeve-like element 35 has formed thereon an eccentric sheave'3lwhich, upon joint rotation of the stem 28 and the sleeve-like element35, varies the degree of communication between the interior of the bore22 and a passage 33 formed in the wall of the body 2|. The passage ,39communicates with a nipple 40 formed on the body 2|, the nipple beingconnectible with the operating conduit Ii of the windshield wiper-motor.

A second annulus 42 is associated with the stem 28 to the right of thesleeve-like e1ement'35 and has cup-like packings 43 and disposed overits opposite ends. The packings 33 and" accordingly define a fluidpassage in the 'bore 22 which,when the control stem 28 is in theillustrated position, establishes a fluid communica- 7;

'tion of the cleaner tion system between the passage 33 and a secondpassage 48 formed in the wall of the body membe;- 2! and spaced axiallywith respect to the passage 38. Theaxial spacing of thepassages "and 48is provided so that, when the control stem 28 is moved to its oppositeor "off" position, the passage 38 is vented to the atmosphere (thiscondition being an incident to successful operation of the motor shownin the prior application referred to above) while the passage 48 issealed by the packing 33.

'I'he passage 48 communicates with a nipple 4! which is connectible witha conduit 53 extending to and in free and open communication with thereservoir It. From the foregoing it will be seen that with-the stem 28and the control knob 38 thereof in the position shown in Fig. l, thefluid pressure differential of the reservoir I5 is connected-with theoperating conduit I l of the motor ll through the conduit same nipple48, the passage 48, the portion of the bore 22 between the packings 33and 43, the passage 38 and the nipple 43. i It will further be seen thatthe effective cross sectional area of this fluid communication may becontrolled by rotation of the eccentrio 31 which is flxedfor rotationwith the conintake manifold l4 exceeds in degree that present in thereservoir IS, the check valve II will be opened and fluid may movedirectly from the conduit 50 into the conduit l6 and the intake manifoldl4. Under this condition the resrvoir i5 serves principally tosupplant-temporary deficiencies of pressure of the intake manifold l4and serves to make uniform a pressure supply which might otherwise varyto an extent sufficient to produce variation in'the speedof operaor eventemporary stoppage thereof.

At its right-hand end as viewed in Fig. l the control stem 28 isprovided with an: annulus 82 which may beheld on the end of the stem 28by forming a rivet head 53 at the end of the stem. A cup leather packing54 is associated with the annulus-.52 at its left-hand face, as seen inFig. 1,'and an axially extending space 55 ismaintained betweenthepacking 44 and thepaoking 84 by means of a compression spring 51which acts between thosepackinga. If desired, washers or'collars i8maybe-interposed between the respective endsj'of the, spring '31 and thepackings and 54. p

When the parts are in they position illustrated,

' that is, when the windshield cleaner is in operation, the right-handend of the bore 22 is vented by means of a passage 33 formed in an endwasher 6| which is disposed over the right-hand end of the'bore 22, inthe illustrated instance by counterboring the body member-2i to receivethe washer 8| and subsequently riveting over the end of the body memberas at 82. This vented condition of the right-hand end of the bore 22 iscommunicated to the parking conduit i2 by means of a passage formed inthe wall of the body member 2i and communicating with a nipple whichconnects with the conduit i2.

When the control 'knob '30 and consequently the stem'28 and the severalpacking elements carried thereby are moved to their extreme right-handposition, as indicated in dot-anddash lines in Fig. l, the packing 33severs the fluid connectionbetween the passages 39 and 48 and,

by'reason of the pace between the packings 44 and. 54,connectsthe-passage 64 with a fluid passage 68 which communicates with anipple 69 and a conduit 10 leading directly to they intake manifold M.

With connection between the conduits "l and I2 thus established, thereservoir l5 will be shut out of the windshield cleaner system so far asthe conduit 50 is concerned and its only connection in the system willbe through the check valve ll of the conduit 16. Accordingly, with thewindshield wiper in parked position, the only change in condition whichcan be effected with respect to the reservoir I5 is a further evacuationthereof by operation of the intake manifold I 4 whenever the fluiddiiferential in the latter exceeds that in the reservoir excepting forwhatever drains are made on the reservoir pressure by other accessories,if such be present. Dissipation of the pressure stored in the reservoirby reason of leakage in the windshield cleaner system, particularly theparking valve, is accordingly effectively eliminated, while parking andholding of the windshield wiper in desired parked position during allperiods of operation of the vehicle engine is satisfactorily eifected byvirtue of the connection established between the conduits and I2.

What is claimed is:

1. A motor vehicle windshield wiper system comprising a sub-atmosphericfluid pressure generator, a vacuum reservoir, a vacuum operatedwindshield cleaner motor having a fluid wiper operating passage and afluid wiper parking and arresting passage, a conduit between said fluidpressure generator and said arresting passage and a conduit between saidreservoir and said operating passage, valve means for rendering said twoconduits selectively eflfective to alternatively connect either of saidpassages with its source of fluid pressure, a conduit between saidgenerator and said reservoir, and a check valve in said conduitpermitting fluid flow from said reservoir to said generator butpreventing retrograde fluid flow, whereby said wiper is parked directlyfrom the generator alone and depletion of the vacuum supply of thereservoir during periods when the wiper is arrested is avoided.

2. A motor vehicle accessory system comprising an internal combustionengine having an intake manifold, a vacuum reservoir, a vacuum actuatedaccessory having a fluid operating passage and a fluid arrestingpassage, a conduit between said manifold and said arresting passage anda conduit between said reservoir and said operating passage, valve meansfor rendering said two conduits selectively effective to alternativelyconnect either of said passages with its source of fluid pressure, aconduit between said manifold and said reservoir, and a check valve insaid conduit permitting free fluid flow from said reservoir to saidmanifold but preventing retrograde fluid flow.

3. A motor vehicle windshield wiper system comprising an internalcombustion engine having an intake manifold, a vacuum reservoir, avacuum operated windshield cleaner motor having a fluid wiper operatingpassag and a fluid wiper parking and, arresting passage, a conduitbetween said manifold and said arresting passage and a conduit betweensaid reservoir and said operating passage, valve means for renderingsaid two conduits selectively efiective to alternatively connect eitherof said passages with its source of fluid pressure, a conduit betweensaid manifold and said reservoir, and a check valve in said conduitpermitting fluid flow from said reservoir to said manifold butpreventing retrograde fluid flow, whereby said wiper is parked directlyfrom the manifold alone and depletion of the vacuum supply of thereservoir during periods when the wiper is arrested is avoided.

ERWIN C. HORTON. ANTON RAPPL.

